NAA is More Effective Than IBA for Rooting Stem Cuttings of Two Nyssa spp.

We conducted two experiments to determine whether Nyssa aquatica and Nyssa ogeche could be propagated from softwood cuttings. In the first experiment, two commercial auxin formulations were used, each at two concentrations. In the second study, we compared root formation among cuttings treated with 3000-ppm indole-3-butyric acid (IBA) in liquid or talc, 3000-ppm 1-naphthaleneacetic acid (NAA) in liquid, and a combination of 1500-ppm IBA and 1500-ppm NAA in liquid. Cuttings were taken from terminal and subterminal positions on juvenile stock plants and held under intermittent mist for six weeks. More terminal cuttings rooted than did subterminal cuttings. A liquid formulation of NAA or NAA and IBA was more effective than IBA at promoting root formation for both species. Up to 93% of cuttings rooted when treated with a solution containing NAA and IBA. Cuttings of N. aquatica treated with NAA in solution produced up to eight times more roots than cuttings treated with no auxin or IBA. For both species, three times more cuttings rooted when treated with IBA in liquid compared to IBA in powder. Results indicate N. aquatica and N. ogeche can be propagated from softwood cuttings, and rooting is enhanced by treating terminal cuttings with NAA in solution.

Impacts of Mechanical Tree Felling on Development of Water Tupelo Regeneration in the Mobile Delta, Alabama

Two water tupelo (Nyssa aquatica L.) stands in the Mobile Delta of Alabama were selected to test the hypothesis that mechanized felling does not reduce establishment and growth of natural water tupelo regeneration relative to traditional tree felling with chainsaws. To test the hypothesis, we established six, 2 ac treatment plots in each of two blocks on each of two sites, and randomly assigned plots to either mechanical tree felling with a tracked, swing feller or chainsaw felling. Each site was clearcut in Fall, 1992, and merchantable boles were removed by helicopter. Establishment and growth of regeneration was assessed prior to harvest and annually for 3 yr after harvest in five, 0.01 ac measurement plots located in each treatment plot. Stand harvesting promoted establishment of water tupelo seedlings such that 3 yr after treatment we recorded over 270/ac on each site regardless of felling method. Seedling height increased at a steady rate and averaged about 39 in. tall after three growing seasons. Woody competition also responded to the harvest, outnumbering water tupelo seedlings 3 yr after treatment by as much as seven to one on Site 2. Water tupelo stump sprouts developing from chainsaw felling grew well and averaged about 13.5 ft tall after three growing seasons. However, mechanical felling reduced water tupelo stump sprouting by 50% leading to a lower density of sprout clumps in mechanically felled plots (P = 0.0253). Our results indicated that mechanical felling techniques used in this study may adversely impact regeneration of water tupelo swamps where coppice is a desirable form of reproduction. South. J. Appl. For. 24(2):65-69.

Stocking Guides for Water Tupelo and Baldcypress

Stocking guides for water tupelo (Nyssa aquatica L.) and baldcypress (Taxodium distichum (L.) Rich.) were developed from published tables of hypothetical stocking and stand development. The form of the stocking guide follows the established paradigm, although the “B”-line is based on the suggested residual stocking in the published table rather than on minimum full stocking determined by open-grown crown area. The stocking guides for water tupelo and baldcypress suggest much greater stand densities than a similar guide for southern bottomland hardwoods. The stocking guides may be used to aid in marking a stand for thinning or to describe stand density for other timber and non-timber management activities. South. J. Appl. For. 19(3):105-108.